Convert from ascii to hex in php

Question

I'm trying to convert from ASCII to HEX in PHP but get a different result to some of the online tools that are available. I know the result I'm looking for so the online tool's result appear to be correct and my code incorrect but I can't work out why.

String:         2Ffbj?DoyXOU
Correct output: 32 46 66 62 6a 3f 44 6f 79 58 4f 55 (from linked site above)
My output:      32 46 66 62 6a 3f 44 6f 79 58 4f 75

My script:

echo bin2hex(utf8_decode("2Ffbj?DoyXOU"));

Where is the fault?

Patrick Maciel · Accepted Answer · 2014-07-04T13:40:45.843

11

Use that:

function ascii2hex($ascii) {
  $hex = '';
  for ($i = 0; $i < strlen($ascii); $i++) {
    $byte = strtoupper(dechex(ord($ascii{$i})));
    $byte = str_repeat('0', 2 - strlen($byte)).$byte;
    $hex.=$byte." ";
  }
  return $hex;
}

The result:

ascii to hex

edited Jul 04 '14 at 13:40

answered Jul 04 '14 at 13:20

Patrick Maciel

4,874
8
40
80

2

Can you explain why the OPs way doesn't return proper result? – Gottlieb Notschnabel Jul 04 '14 at 13:21
1

I was just curious why this algorithm may work while `bin2hex()` won't return proper result. – Gottlieb Notschnabel Jul 04 '14 at 22:22
@GottliebNotschnabel it is not working because bin2hex (and) hex2bin are kind of not what you expect. Bin in php in this case is a string of 0's and 1's eg.: "010110101" not binary data. – Kladskull Dec 22 '21 at 22:24

Taras Kravchuk · Answer 2 · 2021-06-29T08:48:01.373

1

Try this:

function ascii2hex($arg){
   return implode(" ",array_map(fn($x) => sprintf("%02s",strtoupper(dechex(ord($x)))),str_split($arg)));
}

edited Jun 29 '21 at 08:48

answered Jun 29 '21 at 08:35

Taras Kravchuk

11
2

score 0 · Answer 3 · answered Jan 21 '21 at 10:19

Thanks Patrick Maciel for the good answer. Now if use PHP 7.4, there maybe an error message "Array and string offset access syntax with curly braces is no longer supported". Using "[" and "]" to replace "{" and "}" can solve the problem.

Reference: Array and string offset access syntax with curly braces is deprecated

Convert from ascii to hex in php

3 Answers3